In a dry sauté pan, lightly toast chiles (Do not blacken.); cover with water to
soak and remove stems, then drain. In a saucepan, heat oil over high heat. Sauté
onions and garlic until browned. Add cumin, oregano, salt, pepper, chiles and
water. Bring to a simmer, then cook 10 minutes over medium heat. Let mixture
cool, then blend in a blender until smooth. Divide evenly onto 6 plates; serve
with skirt steaks.